Method for non-invasive determination of glycogen stores

ABSTRACT

Provided is a non-invasive method of determining glycogen stores including: receiving an ultrasound scan of at least a portion of a target muscle; and evaluating at least a portion of the ultrasound scan to determine glycogen store within the target muscle.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit under 35 U.S.C. §119(e) of U.S.Provisional Application No. 61/358,778 filed Jun. 25, 2010, thedisclosure of which is incorporated herein by reference.

FIELD OF THE INVENTION

The present invention relates generally to the determination of glycogenstores in animal and human tissue, and more specifically to thenon-invasive determination of muscle glycogen stores.

BACKGROUND

Glycogen is the storage form of glucose in animal and human tissues.Moreover it is the polysaccharide molecule that functions as thesecondary long-term energy store in animal cell tissue and may berepresented as (C₆H₁₀O₅)_(n). Glycogen is made up of glucose buildingblocks, glucose (C₆H₁₂O₆) being a monosaccharide, or simple sugar and animportant carbohydrate in biology. Glycogen is made primarily by theliver and the muscles, but it can also be made by glycogenesis withinthe brain and stomach. Glycogen is analogous to starch in plants, and iscommonly referred to as animal starch, having a similar structure toamylopectin.

Glycogen plays an important role in the glucose cycle as it forms anenergy reserve that can be metabolized quickly to meet a sudden need forglucose. Generally, it is the glycogen stored in the liver that is madeaccessible to other organs and muscles. Muscles themselves utilize theirown stores before drawing from the liver. Within the muscle, glycogen isgenerally found in low concentrations, about 1˜2% of the muscle mass.However, the amount of glycogen stored in a person's body largely isdependent on physical training, metabolic rate and eating habits.

When a meal containing carbohydrates is eaten and digested, bloodglucose levels rise and the pancreas releases insulin. Blood glucoseenters the liver cells and the insulin acts upon the liver cells tostimulate the action of enzymes including glycogen synthase. Glucosemolecules are added together in chains of glycogen so long as the levelsof both insulin and glucose remain plentiful. When needed for energy,the glycogen chains are deconstructed and converted back to glucose.

With respect to muscle tissues, glycogen stores within the musclefunction as an immediate reserve of energy for the muscle, howevermuscle cells lack the specific enzyme glucose-6-phosphatase that isrequired to pass glucose into the blood. As such the glycogen storeswithin a muscle are for the use of that particular muscle and notshared.

Long distance and endurance athletes such as cyclists, marathon runnersand triathletes frequently experience glycogen debt wherein nearly allof the athlete's glycogen stores are depleted after long periods ofexertion without sufficient energy replacement through intake of foodsand supplements. A phenomena commonly referred to as “hitting the wall”it is an experience most amateur and pro athletes seek to avoid for it'sonset usually signals the end of good performance, if not the simpleability to continue participation in the activity.

Developing glycogen stores in the muscles themselves is highly desirablefor many amateur and pro athletes, for the muscle glycogen stores areimmediately available and do not have to be delivered by the circulationof blood from the liver. Significant training and dietary structure canand often is dedicated towards the development and conditioning ofmuscles to produce and store high quantities of glycogen.

How much glycogen is present at the start of an event can therefore be asignificant factor in how a person will perform. For the pro athlete aswell as many amateur athletes, knowledge regarding their glycogenstores, specifically the muscle glycogen stores of key muscles is highlydesirable.

If the stores can be identified as being low, the person can proactivelyeat more carbohydrates. If the stores can be identified as being good,the person can avoid excessive eating—and therefore avoid having bloodtaken from the muscles to the stomach for digestion, as well as thepotentially excess weight of the food or liquids providing thecarbohydrates. More simply put it is important to eat enough but not toomuch, yet where that balance point is can shift throughout the day andfrom day to day.

Present methods for measuring glycogen involve the intrusive process ofbiopsy into the muscle tissue. Though generally a small incision, thisinsult into a finely tuned and trained muscle can cause soreness and orpain, and may well temporarily impede muscle operation as the muscletissue works to repair itself. The resulting pain, soreness and repairprocess may degrade performance during the event or training.

The analysis of a biopsy to determine glycogen store is also a timeconsuming process and by the time the results are known, the metabolismof the body and specifically the muscle may well have changed the levelof muscle glycogen store up or down such that the biopsy determinationcan only be valued as a general gauge of the glycogen levels at a pasttime.

Moreover, the value of determining the glycogen store within a musclemay be entirely offset by the minor injury to the muscle entailed by thebiopsy process if the injury results in degraded muscle performance.Adding to that possibility the latency in biopsy determination and thevalue of intrusive biopsy process is even further diminished.

As such, although such knowledge could be quite advantageous in helpingto insure peak performance for an event or training, present evaluationof glycogen stores are generally educated guesswork based on past biopsytesting. Though helpful, guesswork is clearly not ideal especially forpro athletes and the sponsors of pro athletes who may invest significantsums of money, training time and sacrifice in the effort to be preparedfor a specific event.

Knowledge of muscle glycogen stores is not strictly limited to athletes.Indeed, many people in many different settings could well be aided byknowing their own glycogen stores or the glycogen stores of those theywork with and/or care for. For example the determination of glycogenstores in the muscles of a hospital patient could improve adjustments tohis or care and nutrition. Likewise such knowledge could beneficiallyaid in the care of the elderly or infirm, and persons with certainmedical conditions such as, but not limited to, diabetes might benefitfrom knowing glycogen muscle stores.

Hence there is a need for a method and system that is capable ofproviding non-invasive determination of glycogen stores, and to do so innear real time.

SUMMARY

This invention provides a method and system for non-invasivedetermination of glycogen stores.

In particular, and by way of example only, according to one embodimentof the present invention, provided is a non-invasive method ofdetermining glycogen stores including: receiving an ultrasound scan ofat least a portion of a target muscle; and evaluating at least a portionof the ultrasound scan to determine glycogen store within the targetmuscle.

In yet another embodiment, provided is a non-invasive method ofdetermining glycogen stores including: providing an ultrasound devicehaving a movable transducer, the transducer operable in a high frequencyrange; selecting a target muscle of a subject; adjusting the ultrasounddevice for a depth of scan appropriate for the selected target muscle;disposing the transducer proximate to the subject and perpendicular tothe selected target muscle; scanning the selected target muscle byprocessing ultrasound reflection received by the transducer to provideat least a partial scan of the selected target muscle; selecting an areaof the scan; and evaluating the selected area to determine glycogenstore within the target muscle.

For another embodiment, provided is a method of endurance conditioningfor a subject including: at a plurality of intervals during a period ofendurance activity; disposing a transducer of an adjustable ultrasonicdevice proximate to the subject and perpendicular to a selected targetmuscle, the ultrasonic device adjusted for a depth of scan appropriatefor the target muscle; scanning the selected target muscle by processingultrasound reflection received by the transducer to provide at least apartial scan of the selected target muscle; selecting an area of thescan; evaluating the selected area to determine glycogen store withinthe target muscle; and adjusting the endurance activity to maintain thesubject's glycogen store level at or above a pre-defined minimumglycogen store level.

Further, in yet another embodiment provided is a method for non-invasivedetermination of glycogen stores including: means for receiving anultrasound scan of at least a portion of a target muscle; means fordefining a plurality of areas within the ultrasound scan, each areahaving at least one attribute; means for quantifying each attribute as avalue from a predetermined range of values; and means for processing thevalues to determine a glycogen store.

Still, in yet another embodiment, provided is a system for non-invasivedetermination of glycogen stores including: a glycogen evaluatorstructured and arranged to evaluate at least one selected portion of ascan of a selected target muscle to determine a glycogen store withinthe target muscle.

Further still, in yet another embodiment, provided is a system fornon-invasive determination of glycogen stores including: an ultrasounddevice having a movable transducer, the transducer operable in a highfrequency range, the ultrasound device having an adjustable depth ofscan; a depth of scan selector structured and arranged to select thedepth of scan based upon a selection of a target muscle type; and aglycogen evaluator structured and arranged to evaluate at least oneselected area of a scan of a selected target muscle to determine aglycogen store within the target muscle.

And yet, for another embodiment, provided is a system for non-invasivedetermination of glycogen stores including: a processing unit; a memorystorage device coupled to the processing unit; the processing unit beingadapted to: receive an ultrasound scan of at least a portion of a targetmuscle of a subject; select an area of the scan; and evaluate theselected area to determine glycogen store within the target muscle.

Yet again, for another embodiment, provided is a system for non-invasivedetermination of glycogen stores including: A processor enabled devicehaving at least one output device; an ultrasound device for coupling tothe processor enabled device, the ultrasound device having a movabletransducer, the transducer operable in a high frequency range, theultrasound device having an adjustable depth of scan; a set ofinstructions to adapt the processor enabled device as a glycogenevaluator structured and arranged to evaluate at least one selectedportion of a scan provided by the ultrasound device of a selected targetmuscle to determine a glycogen store within the target muscle and outputthe determined glycogen store.

Further still, in yet another embodiment, provided is a system fornon-invasive determination of glycogen stores including: a processingunit; a memory storage device coupled to the processing unit; anultrasound device having a movable transducer, the transducer operablein a high frequency range, the ultrasound device coupled to theprocessing unit; the processing unit being operative to: receiveidentification of a target muscle of a subject; adjust the ultrasounddevice for a depth of scan appropriate for the selected target muscle;scan the selected target muscle by processing ultrasound reflectionreceived by the transducer to provide at least a partial cross sectionalscan of the selected target muscle; select an area of the scan; andevaluate the selected area to determine glycogen store within the targetmuscle.

And further still, for yet another embodiment, provided is anon-transitory machine readable medium on which is stored a computerprogram for non-invasive determination of glycogen stores including, thecomputer program including instructions which when executed by acomputer system perform the steps of: receiving an ultrasound scan of atarget muscle; and evaluating at least a portion of the ultrasound scanto determine glycogen store within the target muscle.

And yet further, provided for another embodiment is a non-transitorymachine readable medium on which is stored a computer program includinginstructions to adapt a computer system having a processor and anultrasound device with a movable transducer to permit non-invasivedetermination of glycogen stores, the computer program including: aninput routine operatively associated with an input device for permittinga user to enter a target muscle; a depth of scan routine for adjustingthe ultrasound device for a depth of scan appropriate for the targetmuscle; an imaging routine for imaging the selected target muscle byprocessing ultrasound reflection receive by the transducer to provide atleast a partial cross sectional scan of the selected target muscle; adefine portion routine for selecting at least a portion of the scan; andan evaluating routine for evaluating the selected portion to determineglycogen store within the target muscle.

BRIEF DESCRIPTION OF THE DRAWINGS

At least one method and system for non-invasive determination ofglycogen stores will be described, by way of example in the detaileddescription below with particular reference to the accompanying drawingsin which like numerals refer to like elements, and:

FIG. 1 illustrates a high level block diagram of a system fornon-invasive determination of glycogen stores in accordance with atleast one embodiment;

FIG. 2 is a conceptual illustration of an ultrasound scan of a targetmuscle in accordance with at least one embodiment;

FIG. 3 illustrates a high level flow diagram for a method ofnon-invasive determination of glycogen stores in accordance with atleast one embodiment;

FIG. 4 is a refined flow diagram of the evaluating operation fornon-invasive determination of glycogen stores in accordance with atleast one embodiment;

FIG. 5 is a conceptual illustration of an ultrasound scan of a targetmuscle at a first time interval in accordance with at least oneembodiment;

FIG. 6 is a conceptual illustration of the ultrasound scan of FIG. 5with a grid and area attribute valuations in accordance with at leastone embodiment;

FIG. 7 is a conceptual illustration of an ultrasound scan of a targetmuscle at a second time interval with a grid and area attributevaluations in accordance with at least one embodiment;

FIG. 8 is a conceptual illustration of an ultrasound scan of a targetmuscle at a third interval a grid and area attribute valuations inaccordance with at least one embodiment;

FIG. 9 is a conceptual illustration of an ultrasound scan of a targetmuscle at a fourth interval a grid and area attribute valuations inaccordance with at least one embodiment;

FIG. 10 is a conceptual illustration of an ultrasound scan of a targetmuscle further showing an automated selection of an area for evaluationin accordance with at least one embodiment;

FIG. 11 is a conceptual illustration of an ultrasound scan of a targetmuscle further showing a user adjusted/determined selection of an areafor evaluation in accordance with at least one embodiment;

FIG. 12 is a chart of the determined glycogen stores as determined inFIGS. 6, 7, 8 and 9 in accordance with at least one embodiment;

FIG. 13 is a conceptual illustration of an ultrasound scan of a targetmuscle further illustrating a first part having a first threshold valueand a second part having a second threshold value in accordance with atleast one embodiment;

FIG. 14 presents multiple charts illustrating the fatigue and thecomparison of different target muscles in accordance with at least oneembodiment;

FIG. 15 is a block diagram of a computer system in accordance with atleast one embodiment; and

FIGS. 16-18 are conceptual illustrations of alternative configurationsfor a system for non-invasive determination of glycogen stores inaccordance with at least one embodiment.

DETAILED DESCRIPTION

Before proceeding with the detailed description, it is to be appreciatedthat the present teaching is by way of example only, not by limitation.The concepts herein are not limited to use or application with aspecific system or method for non-invasive determination of glycogenstores. Thus although the instrumentalities described herein are for theconvenience of explanation shown and described with respect to exemplaryembodiments, it will be understood and appreciated that the principlesherein may be applied equally in other types of systems and methodsinvolving the non-invasive determination of glycogen stores.

Glycogen is a polysaccharide made up of glucose—a monosaccharide, orsimple sugar and an important carbohydrate in biology. Indeed glycogenis a principle form of energy storage for an animal and thereforereferred to as a “glycogen store.” For ease of discussion andillustration, the embodiments of systems and methods as set forth hereindiscuss and describe non-invasive determination of glycogen stores,though the methods and systems may be applied for the detection of othermonosaccharides or polysaccharides. Indeed, as used herein, the termglycogen is understood and appreciated to include other monosaccharidesor polysaccharides within biological tissue as an energy reserve.

Turning to FIG. 1, presented is a high level block diagram of a systemfor non-invasive determination of glycogen stores (SNDGS) 100.Specifically, SNDS 100 is a glycogen evaluator 102 structured andarranged to evaluate at least one selected portion of a scan 104 of aselected target muscle 106 to determine a glycogen store within thetarget muscle 106.

As used herein the term “scan” is understood and appreciated for itsnormal meaning and as is expected in the medical profession—namely, “a.examination the body or an organ or part, or a biologically activematerial, by means of a scanning technique such as ultrasonography—anultrasound-based diagnostic imaging technique used for visualizingsubcutaneous body structures b. the image so obtained. Moreover the scanmay be the collection of data from a scanner as well as an imagerepresenting that data, but it need not be an image in all cases.

Further the term “evaluate” and it's various derivatives is understoodand appreciated for it's normal meaning, namely, “a. to determine or setthe value or amount of appraise—b. to judge or determine thesignificance, worth or quality of; assess—c. to ascertain the numericalvalue of.” However, with respect to the interpretation of scans, it isnot uncommon to refer to the process of interpretation as analyzing, asin, “a. to separate into constituent parts or elements; determine theelements or essential features of—b. to examine critically, so as tobring out the essential elements or give the essence of—c. to examinecarefully and in detail so as to identify causes, key factors, possibleresults, etc. . . . —d. to subject to mathematical, chemical,grammatical, etc., analysis.” Moreover, as used herein, “evaluate” andit's derivative forms are understood and appreciated to encompass theaspects of “analysis” as may be appropriate for a given situation.

In at least one embodiment, SNDGS 100 has a processor-enabled devicesuch as computer 108. Computer 108 is adapted to receive the scan 104 ofa target muscle 106 of a subject 110, FIG. 1 showing only a portion ofthe subject's right leg.

With respect to FIG. 1, the conceptual illustration suggests the subject110 is a human being. Indeed, embodiments of SNDGS 100 are indeeddirected towards the non-invasive detection and analysis of glycogenstores within human beings, such as for example, elite athletes such asprofessional cyclists, triathletes, speed skaters, swimmers, down hilland slalom skiers, football players, lacrosse players, soccer players,and or other such endurance athletes or individuals such as militarypersonnel, where sustained performance over an extended period of timeis a significant factor in the person's training and conditioning. Itshould also be understood that varying embodiments of SNDGS 100 mightalso be applied to non-human subjects, such as racehorses or otheranimals.

With respect to FIG. 1, SNDGS 100 is at least in part conceptuallyillustrated in the context of an embodiment for a computer program 112.Such a computer program 112 can be provided upon a non-transitorycomputer readable media, such as an optical disc 114 or RAM drive thatcan be provided to a computer 108 to be adapted as SNDGS 100. As isfurther shown and described in connection with FIG. 16, in alternativeembodiments the computer program 112 can be provided to a computerserving at least as part of an application providing platform, such asbut not limited to the Apple App Store, that computer in turn operableto provide the computer program to a computer 108 to be adapted as SNDGS100.

As will be discussed further below, SNDGS 100 may be employed upon acomputer 108 having typical components such as a processor, memory,storage devices and input and output devices. During operation, theSNDGS 100 may be maintained in active memory for enhanced speed andefficiency. In addition, SNDGS 100 may also be operated within acomputer network and may utilize distributed resources.

In at least one embodiment, the SNDGS 100 system is provided as adedicated system to provide non-invasive determination of glycogenstores. In at least one alternative embodiment, the SNDGS 100 system isachieved by adapting an existing computer 108 such as a smart phone(such as an iPhone® or Android®) or tablet computer (such as an iPad®)which is portable.

With respect to FIG. 1, SNDGS 100 has been conceptually illustrated as atablet computer 108, having a display 116 operable to display a visualrepresentation of the scan 104. The display 116 also is shown to providean indicator 118 to inform an operator of the determined glycogen store.

For at least one embodiment, the software may be described as includingan input/receiving routine 120, a define portion routine 122, and anevaluating routine 124. As is set forth and described below, theelements of SNDGS 100 may be summarized or at least one embodiment asfollows.

The input/receiving routine 120 is operable to receive the scan 104,such as a Digital Imaging and Communications in Medicine (DICOM) datafile, and may also receive other information such as the subjects name,location, current state of exertion, etc. . . . The define portionroutine 122 is operable to define a plurality of areas within the scan104 of the target muscle 106. The evaluating routine 124 is operable toevaluate at least one attribute for each of the plurality of areas todetermine the glycogen store within the target muscle.

In addition to the three core routines, input/receiving routine 120,define area routine 122 and the evaluating routine 124 shown with heavyboarders, in at least one alternative embodiment, SNDGS 100 furtherincludes an ultrasound device having a movable transducer 126 operablein a high frequency range and has a an adjustable depth of scan. Morespecifically, the high frequency range is between about 5 to 20megahertz. In addition the depth of scan is between about 1 centimeterand about 7 centimeters. For at least one embodiment, the ultrasoundtransducer 126 is an existing commercially available and FDA approvedultrasound transducer 126 incorporated as part of SNDGS 100 withoutdeparting from the scope of FDA approval for the operation of theultrasound transducer device.

For at least one embodiment of SNDGS 100, the computer program 112 mayadditionally include a depth of scan routine 128, an imaging routine130, and optionally an output routine 132. Moreover, the depth of scanselector routine 128 is operable to adjust the ultrasound device, e.g.,ultrasound transducer 126, for a depth of scan appropriate for thetarget muscle 106. In at least one embodiment, the proper depth of scanis set based on the selection of a target 106 muscle as indicated by anoperator of SNDGS 100.

The imaging routine 130 is operable to direct the movable transducer 126to scan the selected target muscle 106 by processing ultrasoundreflection received by the transducer to provide at least a partialultrasound scan of the selected target muscle. In at least oneembodiment, the imaging routine 130 is structured and arranged tooperate with a third party ultrasound imaging software provided to thecomputer 108.

For at least one embodiment, the optional output routine 132 is operableto output the scan of the target muscle 106 to a storage device, ordatabase. This output routine may also be configured to provide anaudible, visual or tactile output to inform the operator of SNGDS 100 ofthe determined glycogen store for the target muscle 106.

With respect to FIG. 1, it is understood and appreciated that theelements, e.g., input routine 120, define area routine 122, evaluatingroutine 124, depth of scan routine 128, imaging routine 130, outputroutine 132, ultrasound transducer 126 and computer 108 are in at leastone embodiment located within a single device. In at least onealternative embodiment, these elements may be distributed over aplurality of interconnected devices. Further, although each of theseelements has been shown conceptually as an element, it is understood andappreciated that in varying embodiments, each element may be furthersubdivided and/or integrated with one or more other elements.

FIGS. 2 and 3 in connection with FIGS. 1 and 3-13 provide a high levelflow diagram with conceptual illustrations depicting a method 300 fornon-invasive determination of glycogen stores in accordance with atleast one embodiment. It will be appreciated that the described methodneed not be performed in the order in which it is herein described, butthat this description is merely exemplary of one method of non-invasivedetermination of glycogen stores.

As is shown in FIG. 2, the scan 200 may capture a portion of the surfacetissue 202, such as the skin and underlying fat and tissue layers. Thescan 200 may also capture a portion of the deep tissue 206, bone,tendon, organ, or other tissue that is below the target muscle 106.Primarily, the scan 200 captures at least a portion of the target muscle106, more specifically the target muscle tissue 206. Running throughoutthe muscle tissue 206 are various non-muscle tissues 208, such as butnot limited to connective tissues, tendon tissues, and vascular tissues.

As the scan 200 presents at least a cross section of the muscle tissue206, it is understood and appreciated that non-muscle tissue 208 that istruly within, connected to, or in contact with the muscle tissue 206 mayappear as part of, or otherwise within the muscle tissue 206. For thepurposes of non-invasive glycogen store determination as set forthherein, non-muscle tissues 208 that appear within the scan 200 of themuscle tissue 206 may be considered to be part of the muscle tissue 206.

Glycogen stores 210 within the muscle tissue 206 are shown in FIG. 2 andin the accompanying figures as dots, with dot 212 being exemplary. Forconceptual illustration and ease of discussion, the larger the glycogenstore 210 the larger the dot 212. It is to be understood and appreciatedthat muscle glycogen stores 210 are naturally occurring within themuscle tissue 206. Moreover, the methods and systems disclosed hereinfor non-invasive determination of glycogen stores 210 within a targetmuscle 106 are advantageously distinct and directed to naturallyoccurring glycogen stores 210, not injected glycogen as has been used tohighlight internal structures and or features.

With respect to the development of glycogen stores 210, carbohydratesare arguably the most important source of energy for animals, and morespecifically mammals including human beings. Once eaten, carbohydratesare broken down into simple sugars such as glucose, fructose andgalactose that are absorbed by cells and used for energy. Glucose thatis absorbed by a muscle cell but not immediately needed is stored asglycogen, e.g., the glycogen store 210. Muscle conditioning and trainingcan increase the amount of glycogen stores 210. Whether through activityor simply the passage of time between eating or otherwise receivingcarbohydrates or glucose, the glycogen store 210 within muscles will bedepleted.

With respect to the ultrasound scan 200, glycogen stores can be detectedas one or more attributes within the scan 200. More specifically, inmany cases the scan 200 is rendered to a user of an ultrasound scanningsystem as an image. The attributes of the image correspond to sonogramreflection. More specifically, in at least one embodiment the scan 200is represented as an image with attributes represented as luminance,color, contrast and or combinations thereof.

Further, although the accompanying FIGS. 1, and 2, 5-11 and 13 depictthe scan 104 as an image, the interpretation of the scan 104 as an imagehas been chosen to facilitate ease of discussion and illustration.Indeed it is to be understood and appreciated that the in varyingembodiments of systems and methods for non-invasive glycogen detection,attributes of the scan 104 may be interpreted without rendering an imageto a user. Indeed, as is further discussed below other visual, audibleor tactile notifications can be used to signify the determined glycogenstore with or without displaying an image of the scan to a user.

Further, although the illustrations and discussion provided herein forexemplary purposes generally appear to be 2D (two dimensional) images,the system and methods are equally applicable multi-axis ultrasoundimaging techniques, such as for example 3D ultrasound.

FIG. 3 in connection with FIG. 1 provides a high level flow diagram withconceptual illustrations depicting a method 300 for non-invasivedetermination of glycogen stores within a target muscle 106. It will beappreciated that the described method, as well as all other subsequentmethods and refinements to the disclosed methods need not be performedin the order in which they are herein described, but that thedescriptions are merely exemplary of a method or methods that could beperformed for non-invasive glycogen determination.

More specifically, as in FIG. 3, for at least one embodiment, method 300commences with receiving an ultrasound scan 104 of at least a portion ofa target muscle 106, block 302. With the scan 104 received, at least aportion of the ultrasound scan 104 is evaluated to determine theglycogen stores 210 within the target muscle 106, block 304.

For application of method 300, an embodiment of SNDGS 100 need not have,or otherwise be coupled to, an ultrasound transducer 126. Method 300 mayalso be performed by SNDGS 100 when a user desires to review historicaldata of target muscle scans, such as for example to revisit pasthistories of evaluation to perceive changes in development and potentialadjustments to a subject's training methods.

Of course for real time and non-invasive determination of glycogenstores, in varying embodiments SNDGS 100 may indeed include anultrasound transducer 126 as described above. As such, method 300 may beaugmented as method 350, the augmentation as illustrated pertaining toat least one method of providing the received ultrasound scan 104.

More specifically, for augmented method 350, an ultrasound transducer126 is provided as part of SNDGS 100, block 352. A target muscle, e.g.target muscle 106, is selected, block 354. As noted, the ultrasoundtransducer has an adjustable depth for scanning, such as a selectionbetween about 0.5 and 10 centimeters. The ultrasound transducer 126 isadjusted to provide a depth of scan appropriate for the selected targetmuscle, block 356.

In at least one embodiment, the depth of scan is adjusted manually, suchas to about 3.5 centimeters for the rectus femoris muscle. In analternative embodiment, the depth of scan is automatically selected byan operator selecting a muscle, e.g., rectus femoris, vastus lateralis,or biceps. In addition, in varying embodiment, the auto-determined andset depth may also be adjustable by the operator so as to permitadjustment for various body types.

In at least one embodiment additional and optional information about thesubject is recorded, as indicated by dotted block 358. This optionalinformation may include, but is not limited to, details such as thesubjects name, age, gender, time of day, status of subject—at rest/atVOT Max, after eating, or other such information desired to be recordedand displayed in connection with the scanned image of the target muscle.

Moreover, to summarize for at least one embodiment, the augmented method350 includes providing an ultrasound device having a movable transducer,the transducer operable in a high frequency range, selecting a targetmuscle 106 of a subject 110 and adjusting the ultrasound device for adepth of scan appropriate for the selected target muscle 106.

As the ultrasound transducer 126 operates by providing a high frequencysignal that is directed into tissue and detecting reflections returnedby encountered elements, it is understood and appreciated that thetransducer should be aligned generally perpendicular to the selectedtarget muscle. Of course, if a transducer having an alignmentconfiguration that is other than perpendicular is employed the specificalignment as intended for the transducer should be used.

Testing has determined it is substantially immaterial as to whether theultrasound transducer 126 is positioned along the longitudinal orlatitudinal axis of the muscle, or somewhere there between. However forgeneral alignment purposes and ease of operation, in general theoperator of the system will select ultrasound transducer 126 alignmentmatching to either the longitudinal or latitudinal axis of the targetmuscle 106.

Application of the ultrasound transducer 126 against the subjects skincan be a practiced skill, for if too much pressure is applied thetransducer may inadvertently compress the muscle tissue and therebyhamper the quality of the scan and the resulting evaluation of glycogenstores. However, an easy solution presents itself that substantiallyminimizes the risk of transducer related compression of the tissue.

As shown by optional dotted block 360, the subject can simply tense hisor her target muscle 106. More specifically, if the subject acts totense the selected target muscle 106, the natural action of the musclecontraction causes the muscle to swell and thereby resist compression.The contracted and thereby enlarged target muscle 106 may also beadvantageous in providing an even clearer cross sectional scan then maybe obtained with a relaxed muscle.

In short, while the quality of the scan for the tensed or un-tensedtarget muscle 106 may be the same for an operator skilled in how muchpressure to apply, for the novice, as well as the skilled operator,tensing the target muscle 106 does not hamper the determination ofglycogen stores 210 and may help insure greater consistency of scans ina wide variety of locations and settings. Indeed, for at least oneembodiment, when the method of scanning a target muscle 106 isperformed, the subject will tense his or her target muscle 106 as anormal and expected part of the scanning process.

Moreover, to achieve the scan of the target muscle 106, the ultrasoundtransducer 126 is disposed proximate to the target muscle and as theultrasound transducer 126 is activated the target muscle 106 is scanned,block 362. In at least one embodiment the ultrasound transducer 126 isplaced in direct contact with the subject's skin. In at least onealternative embodiment, a protective cover, shield or even the subject'sclothing is disposed between the ultrasound transducer 126 and thetarget muscle 106.

In other words, to summarize for at least one embodiment, the augmentedmethod 350 continues with disposing the transducer proximate to thesubject 110 and perpendicular to the selected target muscle 106, andthen imaging the selected target muscle 106 by processing ultrasoundreflection received by the transducer to provide at least a partial scanof the selected target muscle 106. Many ultrasound transducers provideimages as cross sections of the tissues and structures whereas othersmay provide 3-D views. For consistency in analysis, in at least oneembodiment the operator of SNDGS 100 adopts a convention to scan atarget muscle along its long axis or short axis. For the majority of legand arm muscles the long axis is generally parallel to bone structureand the short axis is generally perpendicular to bone structure. Indeedin some embodiments, scans with SNDGS 100 may be performed substantiallycontemporaneously along both the long and short axis of a target muscle106 for enhanced comparison and analysis.

Method 350 then continues with the evaluation of the scan as discussedabove with respect to block 304. For at least one embodiment, it isunderstood and appreciated that the evaluation of the scan 104 isperformed about contemporaneously with the scanning of the target muscle106.

The determined glycogen store 210 is then reported to the operator,block 364. The determined glycogen store may also be recorded for use inplotting the changes in a subjects glycogen store over time, and or inresponse to various different points of exercise and conditioning aswell as different periods of exertion such as in endurance activities.

In at least one embodiment, the evaluation of the scan to determine theglycogen store with the target muscle 106, is based on the visualexperience of the operator performing the method 300, and or enhancedmethod 350 with respect to a visual image provided by the scan. Morespecifically an experienced individual can provided qualitative analysisof the glycogen store by visually determining an are of the crosssection image to focus on and then evaluating that selected portionbased on historical experience.

Methods 300/350 and or SNDGS 100 can advantageously be utilized by agreater audience of benefitted parties where the evaluation is performedas an automated, or at least partially automated evaluation process.

FIG. 4 in connection with FIGS. 5-13 provides a high level flow diagramwith conceptual illustrations to further refine at least one embodimentof method 400 for evaluating at least a portion of the ultrasound scanto determine glycogen stores 210 within the target muscle 106. Again itis appreciated that the described method need not be performed in theorder in which it is herein described, but that this description ismerely exemplary of one method for non-invasive determination ofglycogen stores within a target muscle.

More specifically, as FIG. 4 expands on FIG. 3, initially a scan of atarget muscle 106 is received, block 302. An exemplary scan such as scan500 is shown in FIG. 5. As previously shown and described with respectto FIG. 2, scan 500 includes skin and or other surface tissue 202, deeptissue 204 and target muscle tissue 206, with elements of non-muscletissue 208. The glycogen store 502 within scan 500 is conceptually shownto be high by the use of large dots 504 providing a substantially darkappearance to the scanned portion of the target muscle tissue 206.

A pre-established glycogen concentration scale 506 is also shown. Thepre-establishment of the glycogen concentration scale 506 aids in theeffective identification of attributes that are correlated to theglycogen store, e.g., color, contrast, darkness, luminance and orcombinations thereof.

In at least one embodiment a precise reference of glycogen store valuesas a gradient scale is established by contemporaneously taking anultrasound cross sectional image and a biopsy of the same target muscleat systematic stages of exercise to exhaust the glycogen stores, and orcarbohydrate replenishment to re-establish the glycogen stores. Theempirical data from a plurality of subject can establish an advantageousreference that is applicable to many different subjects.

It is also understood and appreciated that in at least one embodiment,an even more precise predetermined reference can be established for aspecific subject by the contemporaneous imaging and biopsy process uponthat subject. Alternatively, a general glycogen concentration scale 506as established from one or more other subjects may be refined for aspecific subject based on repeated application of the methods300/350/400 and or SNDGS 100.

As shown the glycogen concentration scale 506 covers a range. For easeof illustration and discussion the exemplary range as shown is from 4 to0. An actual range as applied in methods 300/350/400 and or in SNDGS 100may be greater or smaller. For purposes of the exemplary embodiments anddescription thereof, the valuation of 4 is appreciated to be a glycogenstore of about 100% (e.g., the target muscle is at its maximum glycogenstore) and a valuation of 0 is appreciated to be a glycogen store ofabout 0% (e.g., the target muscle has depleted its glycogen store).

Moreover, as is further discussed below, the glycogen scale—whetherpre-established for a specific subject, or based more generally upondata from a plurality of test subjects permits a user of SNDGS 100 toadvantageously and non-invasively determine the glycogen store within atarget muscle 106. It should also be appreciated that this determinationmay be made upon a subject in nearly any setting or environment. Inother words SNDGS 100 may be used and the glycogen store determined in areal time setting where the subject either is about to engage in anendurance activity or is engaged in training for endurance activity.

To evaluate the glycogen store 502 within the muscle tissue 206, method400 proceeds by defining a plurality of regions within the scan 500. Inat least one embodiment the plurality of regions or parts are aplurality of areas, block 402. These regions or areas can be defined ina variety of ways.

For at least one embodiment, pre-existing scan elements are accepted asthe scan areas, as indicated by optional dotted block 404. In varyingembodiments these pre-existing scan elements are one or more scanpixels. Where the scan is treated as an image, scan pixels may correlatedirectly with image pixels and image pixels may be used as thepre-existing elements.

In an alternative embodiment, as shown in FIG. 6 the plurality of areasare defined by applying a grid 600 to the scan 500. For ease ofillustration and discussion the scan 500 is shown as an image, but it isunderstood and appreciated that the evaluating operation may beperformed by working with the scan 500 as an image or as simply data,neither of which is actually displayed to an operator.

To summarize, for at least one embodiment the evaluating of at least aportion of the ultrasound scan 500 includes defining a plurality ofareas within the ultrasound scan 500, each area having at least oneattribute.

As shown in FIG. 6 the grid 600 is conceptually illustrated as a 12×12grid for ease of illustration, thereby providing one hundred and fortyfour areas 602. In varying embodiments a larger or smaller grid may beapplied. As is further shown in FIG. 6 a subset of the areas 602 is thenselected, block 408.

Moreover, it is not unusual for the sides of the scan to be somewhatunclear, and as shown in FIGS. 5 and 6 there is both surface tissue 202and deep tissue 204 partially captured in the scan 500 in addition tothe desired muscle tissue 206. These undesired areas, of which area 604is exemplary, are therefore removed from further consideration asindicated by the presence of a circled-X in each undesired area.

If not previously set, at least one attribute of the areas 602 is thenselected, such as color, luminance, darkness, contrast or otheridentifiable attribute and/or combinations thereof, block 410. Moreover,the ultrasound scan as a data file may well contain information thatalthough highly beneficial and adaptable for the determination ofglycogen stores is blurred or otherwise rendered less clear when thescan is rendered as an actual image to an operator. As such, it isunderstood and appreciated that non-visual attributes as well as visualattributes may also be utilized alone or in combination with one anotherin varying embodiments for the non-invasive determination of glycogenstores.

In at least one embodiment the attribute of comparison is hypoechoicappearance as opposed to Hyperechoic (also known as echogenic)appearance. More simply stated the evaluation is a comparison of theattributes within an area 602 to a scale of black to white. Again forillustrative purposes the attribute selected in the present example isdot size.

With respect to FIGS. 5 and 6, it is clear that the presence ofnon-muscle tissues 208 affect the apparent concentrations of glycogenstores, e.g., the dots, in some areas but not others. More specifically,exemplary area 606 is shown to have no non-muscle tissue 208 whileexemplary area 608 has a substantial non-muscle tissue 208 component. Inat least one embodiment, the identification and discounting ofnon-muscle tissue 208 is achieved. Moreover this advantageousidentification and discounting can be achieved through the use of athreshold in area evaluation.

To simplify the initial walk through of method 400, initially thethreshold will not be set, decision 412.

Method 400 therefore proceeds to select an area 610 that has not beenremoved from further consideration, block 414. The attribute of thisarea 610 is then quantified as a value, block 416. More specifically theattribute of the selected area 610 is compared to the glycogenconcentration scale 506 and an appropriate value assigned to the area610, shown as the value within the circle—a 3 in the case of area 610.For example exemplary area 606 is quantified as a 4 whereas exemplaryarea 608 is quantified as a 2.

Method 400 proceeds with a query as to whether there are remaining areasto be quantified, decision 418. If additional areas remain, a new areais selected, block 420 and the attribute(s) are again quantified, block416. In at least one embodiment, the selection of the next element isbased on a sweep operation, e.g., starting at the far left and movingacross an entire row before moving then to the next row and startingagain at the far left. This sweep methodology can of course be adaptedto move from right to left and from top to bottom or bottom to top ofcolumns. The sweep method of selection is merely exemplary and is not alimitation precluding alternative selection schemes. Indeed, in at leastone embodiment utilizing multiple processors and/or processes theselection and evaluation of all areas may be performed substantiallysimultaneously.

To summarize again, the evaluating of at least a portion of theultrasound scan 500 includes, for at least a subset of defined areas602, quantifying each attribute as a value from a predetermined range ofvalues.

With the attributes of all areas now quantified as values, the valuesare processed to determine a glycogen store for the target muscle 106 asscanned and represented by scan 500, block 422. Collectively, the valuesassigned to the attributes represent a data set. For at least oneembodiment the processing of the values is an action to determine thecentral tendency of the data set.

Determining the central tendency of a set identifies the “center” of thedistribution of values within the sets. There are three general types ofestimates of central tendency and they are respectively, the mean, themedian and the mode. To compute the mean, it is generally understood totake the sum of the values and divide by the count. This is commonlyknown as averaging. The median is the score found at the middle of theset of values, which is to say that there are as many cases with alarger value as there are cases with a smaller value. The mode is themost frequently occurring value in the set, e.g., the value occurringwith the greatest frequency.

Other options for statistical measures of the values by processing themmay also be performed such as standard deviation and range. Even for anaverage, there are three common choices—arithmetic mean (sum divided bycount), the geometric mean (n member are multiplied together and thentaking the nth root), and the harmonic mean (for a set s of numbers a₁,a₂, . . . a_(n) it is the reciprocal of the arithmetic mean of thereciprocals of a/s).

For various embodiments, processing of the values may also include theapplication of a constant value or other formula. In general and for thevarying embodiments employing different forms of processing for thequantified values, the intent is to achieve a value that isrepresentative of the glycogen store within the target muscle asrepresented by the scan of the muscle tissue.

In at least one embodiment the processing of the values is averaging thevalues, e.g., an arithmetic mean. Moreover, in FIG. 6 a table 612 isshown with columns A˜L and rows 1˜12 correlating to the defined areas602 of scan 500. The quantified values of the selected attribute foreach area are shown and the overall average is shown to be 3.38. Basedon the glycogen concentration scale 506 the determined value of 3.38 attime X₁ is understood and appreciated to be a high glycogen store value.

The determined glycogen store value is then returned, block 424. Invarying embodiments the determined value may be returned to the operatoras the quantified value, or as a representation of the value—such as butnot limited to color, sound, vibration, or combinations thereof as wellas varying intensity thereof.

Use of SNDGS 100 and or method 300/350/400 has many practicalapplications, not the least of which is to assist in athletic and/orendurance training. Another application is for rehabilitation wherein itis highly desirable to quantify how the muscle tissues are repairingand/or rebuilding. Further still, another application would potentiallybenefit incapacitated subjects, such as hospital patients, the infirm,the elderly or other persons who may for one reason or another havedifficulty communicating. As such, for at least one embodiment, themethod and or use of SNDGS 100 may be repeated over time upon the sametarget muscle 106.

FIGS. 7-9 conceptually illustrate repeated testing upon the same targetmuscle at time intervals of X during a subject's workout. As such, notonly do FIGS. 6-9 cooperatively work to demonstrate how the method andor use of SNDGS 100 can advantageously assist in establishing anunderstanding of a subject's glycogen stores over time during exercise,each of FIGS. 6-9 when compared with the other FIGS. 6-9 also can helpaid in understanding how the method and or use of SNDGS 100 canadvantageously identify the glycogen store within a target muscle 106 asthe glycogen itself likely varies in concentration within the targetmuscle.

Further too, it will be observed that the non-muscle tissue 208 variesfrom location to location as between FIGS. 6-9. Moreover the methods andor use of SNDGS 100 can provide a non-invasive determination of glycogenstores within a target muscle 106 even as the scan of the target muscle106 may vary somewhat from one scan to the next.

Moreover, at the second time interval X₂, as shown in the scan 700 ofFIG. 7, the glycogen stores 502 in the deeper portion 750 of the targetmuscle 106 are still generally high. The glycogen stores 502 in theouter portion 752 of the target muscle 106 tissue are beginning todiminish. Indeed prior to the onset of testing of the methods disclosedherein, it was unknown as to whether glycogen stores depleted evenlythroughout, from the outside in or the inside out.

Indeed, although a biopsy of the target muscle can be performed todetect glycogen stores, based on the preliminary findings from testapplications of this method it is clear that even a biopsy could bemisleading—for if the biopsy is taken from too deep or too shallow alocation within the target muscle, the sample may or may not accuratelyrepresent an overall evaluation of the target muscle as a whole. For atleast one embodiment where a biopsy is performed contemporaneously withthe scan of a target muscle such as to establish a baseline for a givensubject, the location of the biopsy within the scan is noted so as tocorrelate the results of the biopsy to a specific area of the scan andthereby permit relative valuation to the other areas of the scan, e.g.,areas 602, 702, 802, 902 based on the results of the biopsy.

Advantageously, and quite distinct from the biopsy, as the entire methodis performed as a non-invasive process, there is no insult to the targetmuscle and therefore no real prospect of the test itself hamperingperformance. Further still, it is possible to quickly and easily comparein near real time the glycogen stores of different muscles, e.g. thesubjects right rectus femoris muscle and the subjects left rectusfemoris muscle. Such information may be highly advantageous during therehabilitation of a muscle or group of muscles.

In other words, the method and or use of SNDGS 100 can enhance theevaluation of glycogen stores within the target muscle that cannoteasily be achieved, if at all matched strictly with muscle biopsy.

As with FIG. 6 a grid 600 has been applied to the scan 700 to define aplurality of areas 702 within the scan 700. Glycogen stores 502 areagain represented as dots of varying sizes. Undesirable areas, of whicharea 704 is exemplary, are again removed from consideration as indicatedby the circle-X.

In accordance with the application of method 400, an area, such asexemplary area 706 is selected and the attributes of this area 706 arecompared to the glycogen concentration scale 506 and an appropriatevalue assigned to area 706, blocks 414 and 416. For example, exemplaryarea 706 is quantified as a 3 whereas exemplary area 708 is quantifiedas a 4.

Again, method 400 proceeds with a query as to whether there areremaining areas to be quantified, decision 418. If additional areasremain, a new area is selected, block 402 and the attribute(s) are againquantified, block 416.

As in FIG. 6, with the attributes of all areas now quantified as values,the values are processed to determine a glycogen store for the targetmuscle 106 as indicated by scan 700. In at least one embodiment theprocessing of the values is averaging the values. Moreover, in FIG. 7 atable 710 is shown with columns A˜L and rows 1˜12 correlating to thedefined areas 702 of scan 700. The quantified values of the selectedattribute for each area are shown and the overall average is shown to be2.99, and indeed a reduction from the scan 500 at time X₁.

In FIG. 8 representing scan 800 at time interval X₃, brief observationindicates that both the deeper portion 850 and the outer portion 852 ofthe target muscle 106 are showing decreased glycogen stores 502.

As with FIGS. 6 and 7 a grid 600 has been applied to the scan 800 todefine a plurality of areas 802 within the scan 800. Undesirable areas,of which area 804 is exemplary are again removed from consideration asindicated by the circle-X.

Again in accordance with the application of method 400, an area, such asexemplary area 806 is selected and the attributes of this area 806 arecompared to the glycogen concentration scale 506 and an appropriatevalue assigned to area 806. For example, exemplary area 806 isquantified as a 2 whereas exemplary area 808 is quantified as a 1.

Again, method 400 proceeds with a query as to whether there areremaining areas to be quantified, decision 418. If additional areasremain, a new area is selected, block 402 and the attribute(s) are againquantified, block 416.

As in FIGS. 6 and 7, with the attributes of all areas now quantified asvalues, the values are processed to determine a glycogen store for thetarget muscle 106 as indicated by scan 800. In at least one embodimentthe processing of the values is averaging the values. Moreover, in FIG.8 a table 810 is shown with columns A˜L and rows 1˜12 correlating to thedefined areas 802 of scan 800. The quantified values of the selectedattribute for each area are shown and the overall average is shown to be1.8, and indeed a reduction from the scan 700 at time X₂.

In FIG. 9 representing scan 900 at time interval X₄, brief observationindicates once again that both the deeper portion 950 and the outerportion 952 of the target muscle 106 are showing decreased glycogenstores 502.

Once again, as with FIGS. 6, 9 and 8 a grid 600 has been applied to thescan 900 to define a plurality of areas 902 within the scan 900.Undesirable areas, of which area 904 is exemplary are again removed fromconsideration as indicated by the circle-X.

Again in accordance with the application of method 400, an area, such asexemplary area 906 is selected and the attributes of this area 906 arecompared to the glycogen concentration scale 506 and an appropriatevalue assigned to area 906. For example, exemplary area 906 isquantified as a 0 whereas exemplary area 908 is quantified as a 1.

Again, method 400 proceed with a query as to whether there are remainingareas to be quantified, decision 418. If additional areas remain, a newarea is selected, block 402 and the attribute(s) are again quantified,block 416.

As in FIGS. 6, 7 and 8 with the attributes of all areas now quantifiedas values, the values are processed to determine a glycogen store forthe target muscle 106 as indicated by scan 900. In at least oneembodiment the processing of the values is averaging the values.Moreover, in FIG. 9 a table 910 is shown with columns A˜L and rows 1˜12correlating to the defined areas 902 of scan 900. The quantified valuesof the selected attribute for each area are shown and the overallaverage is shown to be 0.54, and indeed an even further reduction fromthe scan 800 at time X₃.

With respect to FIGS. 6-9, it is understood and appreciated that assubstantially the same grid 600 is applied to each scan, e.g., scans500, 700, 800 and 900, the same number of areas are defined within eachscan, and the size of the defined areas is generally constant from onescan to the next. This consistency remains and is not affected bydifferent locations of the scan. Certainly for consistency it isdesirable for the operator to attempt to be close and perform each scanin approximately the same location—but slight variation of location isnot detrimental.

In addition, in FIGS. 6-9 and with respect to the evaluating operationof method 400, it has been noted above that undesirable areas areremoved from consideration. In at least one embodiment, the selection ofthe subset of areas for quantified valuation is an automated process.More specifically, as shown in FIG. 10, in at least one embodiment theselection of the portion 1000 for evaluation is determined based uponthe center 1002 of the scanned image of the target muscle 106. Inalternative embodiments the portion 1000 could also be offset from thedetermination of the skin and outer tissue layers or by other generallyestablished reference point.

In at least one alternative embodiment, the selection of the portion forevaluation is user adjustable and or definable. More specifically, forat least one embodiment as shown in FIG. 11, the operator can indicateby a drawn line 1100 the boundary for the selected portion forevaluation. In yet other alternative embodiments, line 1100 may beachieved by stretching and otherwise altering the initial automatedselection, such as portion 1000 in FIG. 10.

FIG. 12 presents a chart 1200 of the determined glycogen stores fortimes X₁˜X₄ as shown in FIGS. 6˜9. Such testing and the resulting chart1200 can be an advantageous tool in athlete conditioning. For example,use of the method and or SNDGS 100 prior to the onset of training andduring training can assist the athlete subject in maximizing his or hertraining efforts, for attempting to exercise or compete with diminishedglycogen stores can accelerate muscle breakdown, increase thepossibility of injury, and potentially subject the subject to otherundesirable conditions.

Moreover, application of the methods and or SNDGS 100 can help determinewhether the subject should eat more carbohydrates before exercising orcompeting, whether his or her glycogen stores are good and furthereating would only divert blood from the muscles to the stomach fordigestion, and or whether despite eating the subject's muscles are notin an optimal condition for exercise or competition and rest should beenjoyed.

Further, as SNDGS 100 permits substantially real time analysis ofglycogen stores, a base line for a subject's metabolism and conversionof foods to glycogen stores can be established. More specifically, byhaving a subject eat food, such as but not limited to bread, fruit,energy supplements such as gels, formulated bars, etc. . . . andscanning one or more target muscles during and after the consumption,SNDGS 100 permits the subject to advantageously know his or her preciseconversion scale for “X” grams of carbohydrates to a “Y” valuation ofglycogen stores in a given amount of time.

Such knowledge of how many grams of carbohydrates equate to a maximumglycogen storage value, and/or the replenishment of that value is highlyadvantageous in many settings. A coach can monitor and adjust the foodintake of his or her individual or team athlete(s), but so too canmilitary personnel better prepare for mission critical situations. Morespecifically, by forecasting the duration of a mission and the level ofexertion during that mission, a commander can accurately predict howmuch food each member of the team should have, for too little and themission may suffer due to fatigue or lack of optimum performance and toomuch may adversely add unnecessary bulk and weight to a team that isstriving to move with speed and stealth.

Moreover, SNDGS 100 and/or methods 300/350/400 are for at least oneembodiment adapted as a method of endurance conditioning for a subject.Specifically, during periods of endurance activity a coach, therapist,trainer, or other person—including the subject, can scan one or moretarget muscles at a plurality of intervals. Typically the first intervalwould be just before starting or at about the onset of the activity. Bytensing the target muscle as noted above, a great consistency for thescan and evaluation is easily achieved. Based on the scan and it'sevaluation the endurance activity may be adjusted—such as to increasethe level of activity, decrease the level of activity or perhaps evenhalt the endurance activity all together.

As the ultrasound scanning process is quick, and can be performed withhand held devices, discussed further below, SNDGS 100 and/or methods300/350/400 can be performed in the filed of the endurance activity. Inother words the subject does not have to travel to a specific facilityor location for the scanning and evaluation to be performed. For examplea cyclist can pause on a trainer or even hold onto a moving car topermit the scan of a target leg muscle. A swimmer may rest at the edgeof the pool or hop out briefly to permit the scan of a target muscle. Arunner may pause on a treadmill or stop on the side of the road. Afootball, soccer, or other field athlete may permit a scan while he orshe is out of rotation. A patient undergoing rehab may be scanned duringthe rehab. Moreover, the glycogen levels of a subject may benon-invasively determined in a setting where such determination ishighly advantageous and contemporaneously applicable to the performanceof the endurance activity.

Returning to the FIGS. 5-9 and the evaluating operation as shown in FIG.4, it is once again noted that throughout the muscle tissue 206 areelements of non-muscle tissue 208, such as but not limited to connectivetissue, vascular tissue, scar tissue, foreign objects, etc. . . . In theinitial review of method 400 it was noted that identifying anddiscounting of non-muscle tissue could be achieved and would likelyenhance the precision for the determination of the glycogen store withinthe target muscle 106.

Returning to FIG. 4, and FIG. 6, in at least one embodiment thiselimination of non-muscle tissue 208 is achieved through the applicationof a threshold in the area evaluation. For the initial pass, a thresholdshould to be set, decision 412. For at least one embodiment, thethreshold may be a user provided value.

Establishing a threshold from the scan itself may be advantageous as thethreshold is then self determined from the scan and can vary from scanto scan, muscle to muscle, subject to subject etc. . . . while stillmaintaining high precision for evaluation.

In at least one embodiment where the threshold is self determined fromthe scan, the method 430 of initializing the threshold substantiallyparallels the above description for the general determination of theglycogen value with respect to block 410—block 418.

Moreover, the method 430 proceeds to select an area 602 that has notbeen removed from further consideration, block 432. The attribute ofthis area 602 is then quantified as a value, block 434. Morespecifically the attribute of the selected area 602 is compared to theglycogen concentration scale 506 and an appropriate value assigned tothe area 602. For example exemplary area 606 is quantified as a 4whereas exemplary area 608 is quantified as a 2.

The method 430 of initializing the threshold proceeds with a query as towhether there are remaining areas to be quantified, decision 436. Ifadditional areas remain, a new area is selected, block 438 and theattribute(s) are again quantified, block 416.

With the attributes of all areas now quantified as values, the valuesare processed to determine a glycogen store for the target muscle 106 asscanned and represented by scan 500, block 422. In at least oneembodiment the processing of the values is averaging the values.Moreover, in FIG. 6 a table 612 is shown with columns A˜L and rows 1˜12correlating to the defined areas 602 of scan 500. The quantified valuesof the selected attribute for each area are shown and the overallaverage is shown to be 3.38.

Although the threshold can be set to be the overall average, asdifferent areas have different concentrations of glycogen due to thepresence or absence of non-muscle tissue 208 as well as state of themuscle tissue itself, in general for at least one embodiment thethreshold is established as a percentage of the initial average value,block 440, such as for example 80%. Moreover, for at least oneembodiment, evaluated areas having an attribute value of at least 3.07(80% of 3.38) are considered muscle tissue while areas having anattribute value of less than 3.07 (80% of 3.38) are considerednon-muscle tissue 208 and therefore eliminated from furtherconsideration.

With a threshold so established, as each area is quantified under block416, the quantified value is now compared to the threshold, inaccordance with method refinement 450. For an embodiment where the samethreshold is to be applied for the entire scan, the previouslydetermined threshold is used, decision 452 and block 454. As will befurther explained momentarily, in at least one alternative embodimentthe threshold is adaptively varied, and more specifically is based thevalues of proximate areas, decision 452 and block 456.

Where the value of the attribute is above the threshold, e.g., greaterthan 3.07 (80% of 3.38), decision 458, the area and its associated valueis maintained, block 460. Where the value of the attribute is below thethreshold, e.g. smaller than 3.07 (80% of 3.38), decision 458, the areaand its associate value are discarded, block 462. Moreover it isunderstood and appreciated that the value of the attribute is comparedto the threshold. Incidental variations of the method to keep the valueif equal to or above in one embodiment or to discard if equal to orbelow in an alternative embodiment are within the scope of thismethodology.

For the example of FIG. 6 there are nine (9) areas with evaluatedattributes rated as 2. For ease of identification, these instances havebeen bolded and centered in table 612 Eliminating these nine valuesleaves ninety one remaining values that are above the threshold, andpermits a refined glycogen store evaluation of 3.90.

Whereas FIGS. 5 and 6 conceptually show the glycogen stores within themuscle tissue to be generally uniform, FIGS. 7-9 conceptually show theglycogen stores within the muscle tissue as being more variable, asapplication of the methods has so determined in repeated testing. Assuch, it is advantageously beneficial for the threshold in at least oneembodiment to be variable.

As suggested by the method refinement 450 for threshold evaluation,initially the threshold can be based on the previously determinedgeneral threshold for the entire scan. However, in at least oneembodiment an adjustable cache for the values of areas proximate to thecurrent area being evaluated is established. Until the cache isestablished, e.g., for the first few passes of evaluation, decision 452,the initial threshold value is used, block 454.

In varying embodiments this cache may be for areas in the same row (Nelements before, after or on either side), areas in the same column (Melements above, below or on either side), areas in the same gridsubsection (M elements by N elements including the currently selectedarea), and or combinations thereof. How the cache of proximate values isestablished—above, below, before, after, around—is largely dependent onhow the areas of the scan are selected for evaluation. In addition, thenumber of values that may be maintained in the cache is at least in partdetermined by the defined size of each area.

With respect to the method refinement 450 for threshold evaluation, ifthe value is above the threshold, decision 458 the area and it's valueare kept, but the value may also be added to the proximate value cache,consisting of N members. As new members are added, old members arediscarded, and in this way the proximate value cache maintains aconsistent record of values for proximate areas.

Moreover, when the next area is selected, block 420 of the evaluationoperation method, as the proximate cache has been established, thethreshold is based on the proximate value cache, block 456. As before,in at least one embodiment, the threshold is a percentage of theproximate value cache. By adopting a percentage, some degree offluctuation between areas is permitted, but a sudden change will standout as tissue substantially unlikely to be muscle tissue.

FIG. 13 conceptually illustrates a scan 1300 of a target muscle 106. Aswith FIGS. 5-9, glycogen stores 502 within the muscle tissue 206 arerepresented as dots of varying sizes. As shown in scan 1300 the deeperportion 1350 of the target muscle 106 has a greater apparent glycogenstore 502 then the outer portion 1352 of the target muscle. As such, ifa constant threshold was applied in the evaluation, areas in the outerportion 1352 might be inadvertently discounted and areas of the deeperportion 1350 might be inadvertently included, and or vis-a-versadepending on the value of the threshold.

An enlarged first section 1302 is shown for the deeper portion 1350.Within this enlarged section a plurality of areas 1304 are shown. Theseareas include muscle tissue 206, but also in some instances non-muscletissue 208. The scale of the areas is such that as shown each area ispredominantly either muscle tissue 206 or non-muscle tissue 208. Withrespect to the glycogen concentration scale 506, the attributes of theareas of predominant muscle tissue are defined as “3” whereas theattributes of the areas of non-muscle tissue are defined as “0.”

By way of example to demonstrate the application of the proximate cachevalue, attention is directed to example row 1306, and currently selectedarea 1308. The proximate value cache from the two areas immediately tothe left of area 1308 are 3. As the attributes of area 1308 are alsoevaluated as a 3, the value of area 1308 is above the threshold,regardless of what percentage is used. Area 1308 and its value are thenkept for the overall glycogen store determination and the value is alsoadded to the proximate value cache, block 460. If the cache is full, theoldest value is discarded and the new value is added.

The selection of the next area is then area 1310. In this case theattributes are evaluated as, for example 0.2. If the threshold is set as80% of the proximate value cache (e.g., 3), the threshold would be2.4—well above the 0.2 of area 1310. Area 1310 is therefore discarded asbeing very likely non-muscle tissue 208, block 462. The same is true forthe next area 1312. However, for the next area 1314 the attributes areevaluated as 2.8 (not shown on FIG. 13) which is above the threshold.Area 1314 is kept and the proximate value cache updated once again,block 460.

Moreover, with a sufficiently fine granularity of defined areas and areasonable proximate value cache, non-muscle tissue 208 can bestatistically identified and eliminated with a reasonable degree ofaccuracy.

Turning now to the enlarged second section 1320 for the outer section,it is clear that areas 1322 are of substantially the same size as areas1304 shown in the enlarged first section 1302. It is also visuallyapparent that with respect to the glycogen concentration scale 506 theattributes of the areas of predominant muscle tissue for the enlargedsecond section 1320 are defined as “1” and again the attributes of theareas of non-muscle tissue are defined as “0.”

To parallel the above example, for enlarged second section 1320attention is directed to example row 1324, and currently selected area1326. The proximate value cache from the two areas immediately to theleft of area 1326 are 1. As the attributes of area 1326 are alsoevaluated as a 1, the value of area 1326 is above the threshold,regardless of what percentage is used. Area 1326 and its value are thenkept for the overall glycogen store determination and the value is alsoadded to the proximate value cache, block 460. If the cache is full, theoldest value is discarded and the new value is added.

The selection of the next area is then area 1328. In this case theattributes are evaluated as, for example 0.1. If the threshold is set as80% of the proximate value cache (e.g., 1), the threshold would be 0.8.While the difference between the areas value and the threshold is not asgreat as the similar example of the enlarged first section 1302, it isstill below the threshold and therefore discarded as being very likelynon-muscle tissue 208, block 462. The same is true for the next area1330. However, for the next area 1332 the attributes are evaluated as0.9 which is above the threshold. Area 1332 is kept and the proximatevalue cache updated once again, block 460.

To summarize the threshold for the enlarged first section 1302 is 2.4whereas the threshold for the enlarged second section 1320 is 0.8, andeach threshold is effective for its proximate location. Moreover, for atleast one embodiment, a first part 1302 of the scan 1300 of the targetmuscle 106 has a first threshold value and a second part 1320 of thescan 1300 of the target muscle 106 has a second threshold value. Foreach, the threshold value is determined from a cache of neighboring areaattribute values.

With respect to applications of SNDGS 100 and or method 300/350/400, fortraining, conditioning, rehabilitation or other purpose, it should beunderstood and appreciated, that the glycogen stores of more than onetarget muscle 106 can be determined. Moreover, the same muscle type,e.g. rectus femoris, vastus lateralis, biceps, etc. . . . , may betargeted in both the left and right legs or left and right arms, chestor back for comparison, and or different muscles from different areasmay be compared. Further still, for each muscle there is also generallya long axis and a short axis, i.e., parallel to the subject's leg or armbone or perpendicular to the subject's leg or arm bone. In varyingembodiments, long axis and short axis scans of the same target musclemay also be compared.

FIG. 14 conceptually illustrates charts from several additionalapplications of SNDGS 100 and or method 300/350/400. In FIG. 1400A, thefirst, second and third scans as evaluated show very little differencefor the target muscle, indicating that the subject is not in a primecondition for continued training (e.g., the muscles are fatigued), andthough he or she may feel fine, heavy exertion may indeed overtax themuscles, and a lesser workout or even rest may be preferable tocontinuing the current exercise routine.

In FIG. 1400B, a scan 1402 of a target muscle in a subject's left leg,e.g. left vastus lateralis, are plotted with the scan 1404 of a targetmuscle in the subject's right leg, e.g., right vastus lateralis which isshown to be similar but faster in depletion as the subject is undergoingrehabilitation.

In FIG. 1400C different target muscles are plotted together, such as therectus femoris 1406 and vastus lateralis 1408 of a subject forcomparison and review of how different muscles are or are not similarlydepleting their respective glycogen stores during active use.

With respect to the above description of SNGDS 100 and methods 300, 350and 400, it is understood and appreciated that the method may berendered in a variety of different forms of code and instruction as maybe preferred for different computer systems and environments. To expandupon the initial suggestion of a processor based device such as acomputer 108 shown in FIG. 1 and discussed above, FIG. 15 is ahigh-level block diagram of an exemplary computer system 1500. Computersystem 1500 has a case 1502, enclosing a main board 1504. The main boardhas a system bus 1506, connection ports 1508, a processing unit, such asCentral Processing Unit (CPU) 1510 and a memory storage device, such asmain memory 1512, and optionally a solid state drive or hard drive 1514and/or CD/DVD ROM drive 1516.

Memory bus 1518 couples main memory 1512 to CPU 1510. A system bus 1506couples hard drive 1514, CD/DVD ROM drive 1516 and connection ports 1508to CPU 1510. Multiple input devices may be provided, such as for examplea mouse 1520 and keyboard 1522. Multiple output devices may also beprovided, such as for example a video display 1524 and a printer (notshown). In varying embodiments, the video display may also be a touchsensitive input device.

Computer system 1500 may be a commercially available system, such as adesktop workstation unit provided by IBM, Dell Computers, Gateway,Apple, Sun Micro Systems, or other computer system provider. Computersystem 1500 may also be a smart phone or tablet computer such as aniPhone or iPad provided by Apple, the HP Slate, the Augen or ArchosAndroid tablets, the Motorola Xoom or other such device. Computer system1500 may also be a networked computer system, wherein memory storagecomponents such as hard drive 1514, additional CPUs 1510 and outputdevices such as printers are provided by physically separate computersystems commonly connected together in the network. Those skilled in theart will understand and appreciate that physical composition ofcomponents and component interconnections comprising computer system1500, and select a computer system 1200 suitable for the schedules to beestablished and maintained.

When computer system 1500 is activated, preferably an operating system1526 will load into main memory 1512 as part of the boot strap startupsequence and ready the computer system 1500 for operation. At thesimplest level, and in the most general sense, the tasks of an operatingsystem fall into specific categories—process management, devicemanagement (including application and user interface management) andmemory management.

In such a computer system 1500, the CPU 1510 is operable to perform oneor more of the methods of non-invasive determination of glycogen storesas described above. Those skilled in the art will understand that acomputer-readable medium 1528 on which is a computer program 1530 fornon-invasive determination of glycogen stores may be provided to thecomputer system 1500. The form of the medium 1528 and language of theprogram 1530 are understood to be appropriate for computer system 1500.Utilizing the memory stores, such as for example one or more hard drives1514 and main system memory 1512, the operable CPU 1502 will read theinstructions provided by the computer program 1530 and operate toperform as SNDGS 100 as described above.

With respect to the various forms of the processor based device, such asthe computer 108, further discussed and described as computer 1500,FIGS. 16-18 present alternative embodiments for the structuralarrangement of components comprising SNDGS 100. More specifically, foralternative SNDGS 1600 as shown in FIG. 16, the ultrasound transducer126 is coupled directly to the computer 108, such that SNDGS 1600 isitself disposed adjacent to the target muscle 106 (not shown).

For alternative SNDGS 1700 shown as FIG. 17, a dedicated processor baseddevice such as a customized computer 1702 is provided, as opposed toadapting a pre-existing smart phone, tablet computer or other computersystem. For SNDGS 1700, the display 116 of SNDGS 1600 is not shown so asto illustrate that alternative output devices such as an indicator 1704,lights 1706, speaker 1708, vibrator 1710 and/or combinations thereof canprovide an operator with an indication of the non-invasively determinedglycogen store. As with SNDGS 1600, the ultrasound transducer 126 may bedirectly coupled to the customized computer 1702, or tethered by acommunications link 1712—wireless or wired as shown.

Further, for yet other embodiments, the computer program 112 to adapt acomputer 108 may be provided directly by enhanced ultrasound transducer1800. More specifically, computer program 112 may be incorporated aspart of the circuit structure 1802 of enhanced ultrasound transducer1800 such that upon connection to computer 108, SNDGS 100 is provided.

As suggested above with respect to FIG. 1, the computer program 112 mayalso be provided by a non-portable media such as a disc 114 to a thirdparty computer, such as computer 1804, providing an application platformsuch as but not limited to the Apple App Store. A user can then connecthis or her computer 108, such as tablet computer 1806 to the third partycomputer 1804 by a network 1808 (wired or wireless) or othercommunication channel and obtain computer program 112 so as to adapt hisor her computer 1806 to perform as SNDGS 100 when a scan of a targetmuscle is provided. In varying embodiments, this scan may be provided bycoupling computer 1806 to ultrasound transducer 126 operated asdescribed above, receiving a scan of a target muscle from internalstorage 1810, or receiving a scan of a target muscle another computersystem 1812 via wired or wireless network 1814, or other appropriatecommunication channel.

Moreover, embodiments of SNDGS 100/1600/1700 are intended for a widerange of subjects. In many instances the primary user of SNDGS100/1600/1700 is a coach or trainer who utilizes SNDGS 100/1600/1700 asan advantageous tool, as he or she can scan target muscles in athletesduring training and test in real time at and during competition,regulations permitting, to better ensure optimum performance. Likewisewith respect to civilian or military medical care, a doctor, nurse,therapist, or caregiver may utilize SNDGS 100/1600/1700 to ensure thatpatents under his or her care are receiving a proper balance ofcarbohydrates and muscle stimulating exercise. Further, a militarycommander and/or training officer can utilize SNDGS 100/1600/1700 toforecast requirements so that operating members of a team during amission have sufficient food resources. And of course use of embodimentsof SNDGS 100/1600/1700 are not strictly limited to human beings. Indeed,horse trainers, zoo veterinarians and other parties may employ the useof embodiments of SNDGS 100/1600/1700 to non-invasively determine theglycogen stores of the animals entrusted to their care.

Changes may be made in the above methods, systems and structures withoutdeparting from the scope hereof. It should thus be noted that the mattercontained in the above description and/or shown in the accompanyingdrawings should be interpreted as illustrative and not in a limitingsense. The following claims are intended to cover all generic andspecific features described herein, as well as all statements of thescope of the present method, system and structure, which, as a matter oflanguage, might be said to fall there between.

What is claimed is:
 1. A non-invasive method of determining glycogenstore value in about real time comprising: receiving a high frequencyultrasound scan of at least a portion of a target muscle; and evaluatingwith a processor at least a portion of the ultrasound scan to determineglycogen store value within the target muscle in about real time.
 2. Themethod of claim 1, further comprising imaging a selected target musclewith an ultrasound device having a movable transducer to provide theultrasound scan of at least a portion of the target muscle.
 3. Themethod of claim 1, wherein the method is repeated over time upon thesame target muscle to determine a range of glycogen stores.
 4. Themethod of claim 1, wherein evaluating at least a portion of theultrasound scan comprises: defining a plurality of areas within theultrasound scan, each area having at least one attribute; for at least asubset of defined areas, quantifying each attribute as a value from apredetermined range of values; and processing the values to determine aglycogen store.
 5. The method of claim 4, wherein processing the valuesis averaging the values to determine a glycogen store.
 6. The method ofclaim 4, wherein a grid is imposed upon at least a portion of theultrasound scan to define the plurality of areas.
 7. The method of claim4, wherein pre-existing elements of the ultrasound scan define theplurality of areas.
 8. The method of claim 7, wherein the pre-existingelements are one or more scan pixels.
 9. The method of claim 1, whereinthe ultrasound scan is an image.
 10. The method of claim 1, adapted asan athlete training method by providing about real-time muscle glycogenstore values to avoid training or competition with diminished glycogenstores.
 11. The method of claim 1, wherein the method is performed inthe field and receiving the ultrasound scan and evaluating the scan todetermine the glycogen store within the target muscle are performedabout contemporaneously and provided to a subject in about real time soas to avoid muscle activity with diminished glycogen stores.
 12. Themethod of claim 1, wherein the method is about contemporaneouslyperformed on different target muscles of a subject.
 13. A computingdevice including a processor configured to perform the method ofdetermining glycogen store within a target muscle as presented inclaim
 1. 14. A non-invasive method of determining glycogen stores valuein about real time comprising: providing an ultrasound device having amovable transducer, the transducer operable in a high frequency range;selecting a target muscle of a subject; adjusting the ultrasound devicefor a depth of scan appropriate for the selected target muscle;disposing the transducer proximate to the subject and perpendicular tothe selected target muscle; scanning the selected target muscle byprocessing ultrasound reflection received by the transducer to provideat least a partial scan of the selected target muscle; selecting an areaof the scan; and evaluating with a processor the selected area todetermine glycogen store value within the target muscle in about realtime.
 15. The method of claim 14, wherein the method is repeated overtime upon the same target muscle to determine a range of glycogenstores.
 16. The method of claim 14, wherein the method is aboutcontemporaneously performed on different target muscles of the samesubject.
 17. The method of claim 14, wherein an image is provided bycorrelating the scan to attributes selected from the group consistingof, luminance, color, contrast, and combinations thereof.
 18. The methodof claim 14, wherein the ultrasound device is adjusted to provide GrayScale output.
 19. The method of claim 14, wherein the selected area isautomatically determined based upon the center of the scan.
 20. Themethod of claim 14, wherein the high frequency range is between about 5to 20 Megahertz.
 21. The method of claim 14, wherein the depth of scanis between about 1 centimeter and about 7 centimeters.
 22. The method ofclaim 14, wherein the depth of scan is adjusted by selecting a type oftarget muscle.
 23. The method of claim 14, wherein a subject tenses theselected target muscle during the scan.
 24. The method of claim 23,wherein the tensing of the selected target muscle minimizes compressionof the target muscle due to disposing of the transducer.
 25. The methodof claim 14, wherein the evaluating includes evaluating the hypoechoicappearance of the selected area.
 26. The method of claim 14, wherein theevaluating is a qualitative analysis.
 27. The method of claim 14,wherein the evaluating is a quantitative analysis, at least oneattribute of the selected area is compared to a predefined reference ofglycogen store values.
 28. The method of claim 27, wherein thepredefined reference is pre-established for the subject being tested.29. The method of claim 14, wherein the evaluating is performed aboutcontemporaneously with the imaging of the selected target muscle and theselecting of the area.
 30. The method of claim 14, wherein evaluating atleast a portion of the ultrasound scan comprises: defining a pluralityof areas within the ultrasound scan, each area having at least oneattribute; quantifying each attribute as a value from a predeterminedrange of values; and processing the values to determine a glycogenstore.
 31. The method of claim 30, wherein processing the values isaveraging the values to determine a glycogen store.
 32. The method ofclaim 30, wherein a grid is imposed upon at least a portion of theultrasound scan to define the plurality of areas.
 33. The method ofclaim 30, wherein pre-existing elements of the ultrasound scan definethe plurality of areas.
 34. The method of claim 33, wherein thepre-existing elements are one or more scan pixels.
 35. The method ofclaim 14, wherein the transducer is placed in direct contact with thesubject and aligned in a first instance to a longitudinal axis of thetarget muscle and in a second instance to a latitudinal axis of thetarget muscle.
 36. A method of endurance conditioning for a subjectcomprising: at a plurality of intervals during a period of enduranceactivity; disposing a transducer of an adjustable ultrasonic deviceproximate to the subject and perpendicular to a selected target muscle,the ultrasonic device adjusted for a depth of scan appropriate for thetarget muscle; scanning the selected target muscle by processingultrasound reflection received by the transducer to provide at least apartial scan of the selected target muscle; selecting an area of thescan; evaluating with a processor the selected area to determineglycogen store within the target muscle in about real time and duringthe period of endurance activity ; and adjusting the endurance activityto maintain the subject's glycogen store level at or above a pre-definedminimum glycogen store level.
 37. The method of claim 36, wherein thesubject tenses the selected target muscle during the scan to reducemuscle compression by the ultrasound device.
 38. The method of claim 36,wherein multiple target muscles are scanned at each interval.
 39. Themethod of claim 36, wherein a first interval is at the onset of theendurance activity and subsequent intervals at about even time intervalsthereafter.
 40. The method of claim 36, wherein adjusting the enduranceactivity is halting further activity.
 41. The method of claim 36,wherein future endurance activity is adjusted based on evaluatedglycogen stores.
 42. The method of claim 36, wherein the subject isselected from the group consisting of professional athletes, militarypersonnel, persons undergoing rehabilitation and or combinationsthereof.
 43. The method of claim 36, wherein each interval of disposingthe transducer, scanning the target muscle, selecting an area andevaluating the selected area is performed in less than about 5 minutes.44. The method of claim 36, wherein the method is performed in the fieldwhere the endurance activity is being performed.
 45. The method of claim36, further including administering a known quantity of carbohydrates tothe subject and measuring a time until a subsequent real-time scan andevaluation show an increase in the glycogen store of the target muscle.46. The method of claim 36, wherein evaluating at least a portion of theultrasound scan comprises: defining a plurality of areas within theultrasound scan, each area having at least one attribute; for at least asubset of defined areas, quantifying each attribute as a value from apredetermined range of values; and processing the values to determine aglycogen store in about real time.
 47. A system for non-invasivedetermination of glycogen stores value in about real time comprising:means for receiving an ultrasound scan of at least a portion of a targetmuscle; means for defining a plurality of areas within the ultrasoundscan, each area having at least one attribute; means for quantifyingeach attribute as a value from a predetermined range of values; andmeans for processing the values to determine a glycogen store value inabout real time.
 48. The system of claim 47, further comprising imagingmeans for imaging a selected target muscle with an ultrasound devicehaving a movable transducer to provide the ultrasound scan of at least aportion of the target muscle.
 49. The system of claim 47, wherein a gridis imposed upon at least a portion of the ultrasound scan to define theplurality of areas.
 50. The system of claim 47, wherein pre-existingelements of the ultrasound scan define the plurality of areas.